Usually, belt buckles are anchored to the vehicle seat or to the vehicle floor by flexible traction cables which, following insertion of the buckle tongue in the buckle head, permit alignment of the belt buckle to approximate the run of the belt webbing. The lower the forces opposing the lateral deflection of the belt buckle, the better the orientation of the belt buckle can be adapted to the run of the belt webbing. When, however, a slight bending moment opposes the lateral deflection of the belt buckle, the belt buckle may laterally deviate on insertion of the buckle tongue, thus making it necessary to design the flexural strength of the buckle anchorage greater than it would be desirable for an optimum run of the belt webbing.